Method and means for soldering conductors



July 29, 1958 R. w. TRICKLE, JR 2,845,521

METHOD AND MEANS FOR SOLDERING CONDUCTORS Filed April 22, 1955 INVENTORRUSSELL W. TRICKLE, Jr.

ATTORNEYS United States Patent METHOD AND MEANS FOR SOLDERING CONDUCTORSRussell W. Trickle, Jr., Janesville, Wis., assignor to Dittmore-FreimuthCorp., Milwaukee, Wis., a corporation of Wisconsin This inventionrelates to the joining of electrical and electronic conductors.

The invention relates particularly to the soldering of conductor ends toobtain a butt type joint in which the wires do not overlap. This type ofbutt joint is desirable in various kinds of electronic work, such forexample, as the joining of the center conductor in a coaxial cablesplice since the center conductor must be joined with little or nochange in electrical characteristics and mechanical strength.

When joining such conductors, particularly of the smaller diameters,difiiculty has been encountered in aligning the ends. for a butt typejoint, since the conductors are usually composed of strands or solid ortubular conducting material or of copper covered steel wires commonlycalled copper-weld. It has been difficult not only to hold these smalland highly flexible conductor ends in abutted relation but also to applythe solder in a manner to avoid the formation ofan enlarged solder jointor splice that has to be dressed down to the diameter of the conductorends.

The principal object of the invention is to provide a new method andmeans by which either a straight splice or a T-splice may be quickly,easily and inexpensively made without. the necessity of special skillon. the part of the operator.

Another object of the invention is to provide a simple and inexpensivetubular connector of breakable material which will aid in aligning theconductors, prevent small flexible conductors from being bent out ofalignment, prevent the intermingling of the strands of strandedconductors and thereby increasing the size of the joint, and prevent thesolder from building up to a larger diameter than the rest of theconductor and hence eliminate the need for dressing the soldered jointor splice.

Another object is to provide a conductor holder or connector of theabove indicated character made of a ceramic or equivalent brittle andfrangible material so that after it has served' its purpose, it may bereadily crushed and removed from the soldered joint.

Another object is to provide such a tubular or beadlike connector whichwill enable a third conductor to be united with the aligned conductorends to provide a T- splice or joint such as quite commonly used in thecommunity T. V. systems.

With the above and other objects and advantages in view, the inventionresides in the novel combinations and arrangements of parts and thenovel features of construction hereinafter described and claimed, andillustrated in the accompanying drawings which show the presentpreferred embodiment of the invention.

In the drawings:

Fig. l is a view of two opposed conductor ends with portions of theirinsulating covering being stripped back, the one at the left beinginside elevation and the one at the right in longitudinal section;

Fig. 2 is an enlarged top view of a breakable bead or connector;

Patented July 29, 1958 Fig. 3 is a transverse section taken on line 3-3in Fig. 2;

Fig. 4 is a longitudinal section through the connector tube or beadshowing it applied to the ends of two conductors tobe joined and readyfor the heating and soldering operations;

Fig. 5 is a view similar to Fig. 4 but showing the jaws of an electricsoldering transformer applied to the two conductor ends, the connectortube being in elevation;

Fig. 6 is an elevation of the solderedcon'ductor as it appears when theconnector tube has been broken off of the splice; and

Fig. 7 is a view similar to Fig. 4 but showing a third conductorarranged to form a T-splice or joint.

Referring more in detail to the drawings the numerals 10 and 11 denotetwo similar electrical conductor wires the ends of which are to besoldered in a butt type joint. The wires may be covered by any suitableinsulation 12; and if so, the insulation is stripped back from the endportions of the conductors, as seen in Figs. 1, 4 and 5, to enable themethod to be carried out. The conductor wires are usually of copper andmay be solid or tubular or copper covered steel, and they may becomposed of fine strands twisted or braided together. The invention isparticularly useful in butt soldering conductors of smaller sizes suchas /e" diameter or less since their bared ends are quite flexible andhence difficult to hold in. abutted relation.

In thepractice of the invention the baredends of the conductors areinserted in the opposite ends of a holding element 13 which ispreferably of tubular shape and made of a readily breakable material sothat it may be easily crushed and removed after it has serveditspurpose; This disposable molding device or connector element. may beof elongated cylindrical shape and has a straight continuous bore 14 ofa diameter corresponding to that of the conductors so that they willhave an easy fit therein and may be pushed into the ends. Formed in thetubular connector, preferably midway of its ends, is a circular radiallyextending opening or hole 15 which preferably has the same diameter asthe bore, as seen in Fig. 3. The conductor ends are pushed into theconnector 13 so that their extremities will abut or substantially abutat a point opposite the hole 15 as shown in Fig. 4. The primary purposeof the hole opening 15 is to permit solder to be applied to the abuttedconductor ends, and that is preferably done after the ends of the wireshave been heated, as later described. The tubular connector ispreferably made of ceramic material but it may be made of any moldableplastic such as glass or other refractory material which is brittle orfrangible so that the device may be easily cracked off of the solderedjoint with a pair of pliers or other tool by crushing it. The bead orconnector 13 will be made in dififerent sizes according to the sizes ofthe conductors to be joined. If the device is to connect conductor Wiresof small diameter such as A3" or less, it need not be longer than andthe thickness of its wall may be about .062".

While for some purposes a soft solder may be used, it is preferable touse silver solder which has a melting point lower than that of theconductor wires and to heat the conductor ends before applying thesolder. The heating is preferably done by passing an electric currentthrough the conductors. That may be done by the use of an electricsoldering transformer 16, a portion of which is shown in Fig. 5. Such asoldering transformer is disclosed in application Serial No. 485,404,filed February 1, 1955, in which I am one of the joint applicants, theapplication having matured in Patent No. 2,771,540 issued November 12,1956. The transformer includes two pairs 17 and 18 of opposed terminaljaws adapted to be clamped on the conductor ends 10 and 11 at or 3.adjacent the ends of the connector. The jaws are tightened on the endsby screws 19, and when the current is applied to the transformer, heatdevelopsinside the ceramic bead between the conductor ends. The silversolder is applied through the hole and allowed to flow for a'fewseconds. The current is then turned off and the jaws 17 and 18 aredisconnected from the wires. The ceramic bead or connector may then becracked off with a pair of pliers by crushing it, leaving the completedjoint with the solder 20 connecting the wires.

If it is desired to make a T-splice, the same procedure is carried outbut while the solder is in a molten condition the bared end 21 of athird conductor is inserted in the hole 15, as seen in Fig. 7 so thatthe ends of the three conductors will be united by the solder. Thecurrent is then turned off and when the solder is hard the ceramic beadmay be removed. A suitable soldering flux may, of course, be used in thesoldering operation.

It will be seen that the use of the invention will enable an unskilledperson to quickly and easily produce either a straight or a T-splice inwhich the soldered portion of the joint will have practically the samediameter as the conductor wires that are joined, and hence the jointwill have substantially the same mechanical strength and electricalcharacteristics of the other portions of the conductors. The use of thebead aids in aligning the ends of the conductors, and with smallflexible conductors supports them while they are hot so that they do notbend out of alignment. With stranded conductors it prevents the strandsfrom intermingling and increasing the size of the joint. With largerrelatively stiff conductors, the use of the device enables the joint tobe formed so that it will have the same diameter as that of the rest ofthe conductor and hence no dressing of the joint will be necessary.

From the foregoing, taken in connection with the accompanying drawing,it will be seen that novel and advantageous provision has been made forcarrying out the objects of the invention, and while preferences havebeen disclosed, attention is invited to the possibilty of makingvariations within the scope of the invention as claimed.

I claim:

'1. As an article of manufacture, a disposable molding device for use inmakinga soldered joint between small size electric and electronicconductors which are highly .4 flexible and provide a molded splicehaving the same diameter as the joined conductors, said devicecomprising a one piece tubular element into the ends of which two baredconductors may be pushed, said element being made of brittle frangiblematerial and having a continuous bore of a diameter corresponding tothat of the conductors to hold the latter axially alined and againstflexing, said bore being intersected by a radial opening in the elementopposite which the conductor ends may be abutted, said opening being ofsufficient size to permit solder to be introduced through it into saidbore to unite the abutted conductor ends when they are electricallyheated, the brittleness of said element permitting it to be readilycrushed and broken away after the solder hardens to leave a splicehaving the same diameter as that of the joined conductors.

2. The hereindescribed disposable mold for use in making a solderedjoint between highly flexible electronic conductors having a diameter of3 8" or less and to provide a molded splice having the same diameter asthe joined conductors, comprising a straight one-piece cylindrical bodyof tubular form with a continuous cylindrical bore and with a circularradially extending opening in communication with the bore adjacent thecenter of the body, said bore having the same diameter as theconductors, whereby when two conductors are pushed into the ends of thebore and their extremities abutted at said opening the conductors willbe held in axial alinemerit and prevented from flexing, said radialopening also having the same diameter as the conductors to permit solderto be introduced into the opening at the abutted conductor ends to unitethem when they are electrically heated, and to permit the bared end of athird conductor to be pushed into the molten solder in the opening toform a T-splice in which all solder parts have the same diameter as thethree conductors.

References Cited in the file of this patent UNITED STATES PATENTS355,611 Howson Jan. 4, 1887 653,033 McIntire July 3, 1900 2,618,234Armacost Nov. 18, 1952 2,677,746 Duch et a1. May 4, 1954 FOREIGN PATENTS151,921 Austria Dec. 10, 1937

